Symbol: ESsquare
drivers/tty/vt/vt.c
2395
vc->vc_state = ESsquare;
drivers/tty/vt/vt.c
2412
vc->vc_state = ESsquare;
drivers/tty/vt/vt.c
2703
case ESsquare: /* ESC [ aka CSI, parameters or modifiers expected */